1. Which Bethesda Softworks game is it from?
The Elder Scrolls Legend: Battlespire. Released in 1997, Battlespire was, I believe, the first Elder Scrolls title that supported multiplayer. Check out UESP’s Battlespire page for more about the game.

2. What is the sound of?
It’s the Scamp!

3. Extra 1,000,000 points if you can name the developer who created the “source” of the sound in the game. (Not the actual sound itself — though if you know the answer to that, kudos).
Mark Jones is the artist who created the Scamp. Elder Scrolls aficionados will recognize his name. Mark has worked on most of the Elder Scrolls games.